Washable wall paper



April 17, 1934. c FLECK 1,955,626

WASHABLE WALL PAPER Filed May a1, 1933 Patented Apr. l7, i934 par waspsWALK. mean Louis C. Fleck, Appleton, Wia, assignor to Paper PatentsCompany, l lfl Wis, a corporation of Wisconsin Application May 31 1933,Serial No. 873,721

3 (Claims. (oi. 92-40) My invention relates to decorative paperespecially suitable for use as wall covering and has to do moreparticularly with an improved paper having a water-resistant surface andcapable of resisting moderate rubbing with a damp cloth, so that it mayreadily be cleansed.

' A particular object of my invention is to provide an article of theclass referred to which may be made from inexpensive materials and.which I is highly satisfactory for all desired purposes.

A further object is to provide a simple and inexpensive process forproducing the above-described article.

Further objects and advantages will" become apparent as the descriptionproceeds.

Referring to the drawing forming part of this specification andillustrating a preferred embodiment of my invention:

Figure 1 is a plan view of a portion of decoraso tive paper made inaccordance with my invention,

and

Figures 2 to 6 inclusive are sectional views on an enlarged scale of thesame in various stages of manufacture. i 1

My improved process may be practiced as follows:

(1) Coating.-A web of low-cost paper base 10, usually including asubstantial proportion of ground wood, which is ordinarily not colorfast to light, is coated with a filler 12, such as clay, blanc fixe,barytes, or calcium sulphate, and a potentially water-resistant binder,such as casein, casein and formaldehyde, rosin and starch, or linseedoil and starch. The filler is applied as an aqueous mixture, sufiicientcoating being applied to render the paper light-resistant.

This coating step may be carried out according to known methodssubsequent to the forming of the paper on the usual paper machine; or inthe course of manufacturing the paper web on the paper machine. 7

The amount of coating material is preferably at least 9 pounds,including mineral and binder, per 24 x 36500 sheet ream, the bindercomprising approximately per cent of the coating.

After the coating has been applied the web is preferably dried,although, where all steps are carried out as a train, the drying neednot be completed.

(2) Printing.The second step consists of printing the design on the web,prepared as above described, with a potentially waterproof water ink 13.For this purpose there may be used aqueous suspensions of pigments, orpigments with fillers, such as clay, or colored fillers, etc.,

and binding material such as casein, or casein andhexamethylenetetramine, or casein and formaldehyde, or rosin and casein,or linseed oil and casein, etc. After the printing, this paper may bepartly or entirely dried. (3) FiringP-In the final step the potentialwater resistance of the binders used in the first and second steps isdeveloped or fixed by treating the web with a solution of a fixingagent, such as alum, aluminum acetate, or alum and formaldehyde, etc.which will react with the binders to convert them into water resistantsubstances 14. In the cases where formaldehyde or hexamethylenetetraminewas used in the first or second steps, the acidity of the aluminum saltsolution 7o will render them active. At the conclusion of thisstep thepaper is dried.

The product ofthe process as so far described I is a now-glossy, fairlywater-resistant paper.

If a glossy surface 15 is desired it may be obtained by applying slightquantities of emulsions of waxes such as Carnauba or Montan waxes, tothe coated surface, and polishing it by .means of brushes. Or such asurface may also be obtained by calendering, friction glazing, etc.

Example The following is a specific example of a preferred embodiment ofmy invention:

I. Paper with a furnish of approximately 5 v 1 Percent No. 1 dryunbleached spruce 25 No. 1 wet unbleached spruce 10 No. 1 ground wood 65Clay 5 Size 2.0

Alum 4.0

is coated in manufacture with potentially a water-resistant coating,such as casein and formaldehyde and clay, or rosin and starch and clay,or linseed oil and starch and clay. A

typical coating solution is as follows:

# casein.

Add 9 pounds, 8 ouncesof ammonia water (sp. gr. 0.90) to casein solutionand 3 pounds of borax which has been dissolved in 2 gallons of water.Heat this mixture to 120 F. Then add 7 pounds of pine oil (used toprevent foaming) and 4 pounds of formaldehyde. (40% solution).

The finished casein solution is then added to and mixed with the clayslip solution.

Sufiicient coating of this mixture is then applied to the paper web onthe paper machine to give the finished paper resistance to fading. Thisamounts to approximately 10 pounds per 24x36-- 500 sheet ream basis.

II. In my preferred embodiments, designs or patterns are printed on thedry paper with water ink.

A typical ink formula is as follows:-

Casein solution for binder Color paste (formula varied according toparticular pigment used) Water 9 lbs. 10 ozs. I-Ielio fast red RLD paste'11 lbs. 6 ozs. Clay 21 lbs. Casein solution (formula given above) 40lbs. Pine oil cc.

Casein solution Mix thoroughly and soak for twenty minutes:

Lbs. Water at 65 C 54 Casein (30 mesh California) 20 Add a solution of:

' Lbs. Water at 80 C 12 Borax 3 Add a solution of Lbs. Water at 60 C 4A; Soda ash /2 The temperature of the casein solution should now be 55to 60 C. Hold at this temperature for at least one-half hour, or untilperfectly smooth. Cool to about 30 C. (not higher than 35 0.).

Add a solution of:

Lbs. Ozs. Cold water 5 6 Hexamethylenetetramine 1 9 III. The third stepinvolves treating the printed Various modifications coming within thespirit of my invention will doubtless suggest themselves to thoseskilled in the art. Hence, I do not wish to be limited to the specificembodiments described herein except to the extent indicated by theappended claims, which are to be interpreted as broadly as the state ofthe art will permit.

I claim as my invention:

1. A water-resistant decorated paper, comprising a paper base includinga filler, said paper being printed upon with a water ink, said fillerand ink containing a chemical binder, and said binder being chemicallyfixed to render said printing surface resistant to water.

2. A method of producing an article of the class described, comprisingforming a paper web with a filler carrying a potentially water-resistantbinder, at least partially drying the paper web, printing upon said webwith a water ink also containing a potentially water-resistant binder,and treating said web so as to fix said binder and render the surface ofthe paper water-resistant.

3. A method of producing an article of the class described, comprisingforming a paper web and coating same with a filler containing mineraland a potentially water-resistant binder, at least partially drying thepaper web, printing upon said web with a water ink also containing apotentially water-resistant binder, and treating said web so as to fixsaid binder and render the surface of the paper water resistant.

